Dismantling a Rear Caliper.(piston removel help req'd)

Can you help? I swapped mine out on Friday with one I aquired from falc as the pistions didn't move at all, no mater what you did with the leaver. Can anyone give me some ideas as to how to get the pistions out? I've tride heating it all up in boiling water, but they still wouldn't shift.
I'm not bothered about trashing the seals as I have a replacement set, at this rate I'll be blow-torching them.

[northwind]

Got an airline? That's how I do it now, but I used to veeeery carefully use my humungous mole grips, and a twisting motion.

That, or fit them to the m/c and squeeze them out naturally...

I did think about that now that I've cleaned them up a bit, but they didn't move before and so I think they might not move now. No I don't have a air line, might have to see if I can find someone who does. Did try a can of air but I can't get a decent seal...

[northwind]

Yeah, I doubt you could do it with a can, it takes a lot of pressure to get them out (I shot a GSXR front caliper piston about 4 inches into the ground once, kind of glad it wasn't pointing upwards or I'd never seen it again!)

I put 8 bar worth of air pressure into a caliper once and it didn't move. i ended up buying a tool from machine mart that pushes the pistons in

i reconnected the system again used the tool to hold one piston while i pumped the lever to get the other out, when both pistons where free enough i split the caliper and finished it off with the air. failing that, take it you a garage and ask if they can pull it out with a blind bearing puller, machine mart have thoose to but there £80+, it's like a slide hammer with a set of internal gripping jaws

Oooohh... I think I might just try putting it on the other SV...